国产三尖瓣成形环治疗功能性三尖瓣反流的近中期疗效观察

目的观察国产三尖瓣成形环在治疗功能性三尖瓣反流近中期的效果。方法 61例功能性三尖瓣反流患者分为De Vega成形术组（23例）和人工成形环组（38例）,比较两组术前及术后7 d、3个月、6个月、1 a三尖瓣反流面积、肺动脉收缩压、左心室射血分数、右心室内径、右心房内径和心功能。结果所有患者均治愈出院。两组术后各随访时点三尖瓣反流面积、肺动脉收缩压、左心室射血分数、右心室内径、右心房内径和心功能变化较术前明显改善,差异有统计学意义（P〈0.01）,中期上述指标人工成形环组要优于De Vega成形术组（P〈0.01或0.05）。结论三尖瓣成形术是治疗功能性三尖瓣反流的有效方法,人工成形环对术后功能性三尖瓣反流中期改善程度优于De Vega成形术。     

等效电荷变换法及其在量子环研究中的应用

利用等效电荷变换法,把三维空间中的杂质电荷对位于X-Y平面上量子环的影响,用一个在X-Y平面上（或X轴上）的虚拟等效电荷取代,从而使计算简化,对结果的分析更加清晰,物理图像更加明确.     

基于Delaunay三角网的GNSS控制网闭合环自动搜索算法研究及应用

计算GNSS控制网的同步环和异步环的闭合差是衡量GNSS控制网测量精度的重要依据,然而某些商业GNSS软件不能完全搜索所有闭合环.在建立Delaunay三角网基础上,提出了一种新的GNSS控制网闭合环自动搜索算法,并根据此算法采用C#语言编写软件.结果表明,该算法实现了GNSS控制网所有闭合环的闭合差快速计算和检核,提高了GNSS控制网测量精度,丰富了农业生产实践作业效率.     

Influence of growth ring angle,adhesive system and viscosity on the shear strength of adhesive bonds

Abstract

To investigate the influence of growth ring angle, adhesive system and viscosity on the bonding properties of adhesive bonds, shear tension tests according to DIN EN 302-1 (2004) were conducted using one-component moisture-curing polyurethane, polyvinylacetate and urea-formaldehyde. Significant differences between the systems could be detected, which were reflected in the predominant failure behaviour for each system. Specimens showing wood failure were influenced mainly by the wood factors, whereas samples which had failed in the adhesive part of the bond differed only in the adhesive properties. The growth ring angle showed the same tendencies as it does in plain wood. Therefore, to gain more information on the adhesive performance in the bond, a loading along the LT plane seems more appropriate for beech wood used in DIN EN 302-1 (2004).     

Similarities and differences between Amaranthus species and cultivars and estimation of outcrossing rate on the basis of electrophoretic separations of urea-soluble seed proteins

Wheat-rye translocation line (2BS/2RL) has been developed for resistance to biotype L of Hessian fly and agronomically useful traits. AFLP analysis using 64 primer pairs was conducted in order to identify 2RL-specific polymorphisms between “Coker 797” (non-2RL), near-isogenic line (NIL) carrying 2RL, and “Hamlet”. Nine primer combinations identified twelve reproducible polymorphic fragments in the NIL carrying 2RL. These twelve fragments were cloned and sequenced with an aim towards converting AFLP markers into sequence tagged sites (STS). A comparison of the 12 sequences with non-redundant accessions in the NCBI database using the BLAST search option indicated that one fragment of approximately 200 bp in length (amplified using primer combination E+AAC / M+CTA) was highly homologous with the rye-specific repetitive sequence R173-1 and Wis-2-lA, a retrotransposon-like element in wheat. Two STS primers (SJ07 and SJ09) out of twelve STS primer sets enabled the detection of polymorphisms between Coker 797 and NIL carrying 2RL. In order to verify whether the polymorphism detected by primers SJ07 and SJ09 was in fact the result of the presence of 2RL, additional plant material was examined. Amplified products of about 260 bp fragment with the SJ07 primer set were generated in rye cvs.“Chilbohomil” and “Jochunhomil”, triticale experimental line Suwon 15, and wheat experimental line K-14 (1AL/1RS & 2BS/2RL), as well as NIL carrying 2RL and Hamlet, but not in Coker 797 (non-2RL), “Keumgangmil” (non-translocation wheat), KS92WGRC17 (PI592729 /;/ 6BS/6BL-6RL), KS92WGRC19 (P1592731 /;/ 4BS/4BL-6RL), “TAM200” (1AL/1RS), and “Siouxland” (1BL/1RS). Our data suggest that primer set SJ07 amplifies a “2RL-specific” fragment of diagnostic value. This revised version was published online in August 2006 with corrections to the Cover Date.     

ANALYTICAL SOLUTION OF RING SHELL LINING WITH ANNULARLY VERTICAL WALLS MADE CONTACT WITH SURROUNDING ROCK

In this paper,the ring shell lining with annularly verticalwalls made contact with the surrounding rock is considered as a combinationstructure formed of ring shell,inner and outer annular barrels on elastic fo-undation.The complex equation and its solutions of ring shell under deadload of lining and vertical and horizontal surrounding rock pressures are de-rived by the method of complex function.The governing equation and itssolution of the barrels on elastic foundation are also derived by theory ofcylindrical shell.And then,the ring shell lining is assembled by the subst-ructures by means of compatibility conditions of internal forces and defor-mations between them.In the paper,all formulas for the practical computa-tion in engineering are derived,the numerical examples are given and theeffects of the parameters of the lining on the work behaviours of lining alsoare discussed preliminarily     

Assessment of sugar maple tree growth in relation to the partitioning of elements in xylem along a soil acidity gradient

Partitioning of elements in tree xylem is being increasingly studied, as it suggests that elements are potentially mobile within the xylem long after their uptake. A recent study revealed that only the most mobile xylem fraction (water-soluble) of base cations (calcium [Ca], magnesium [Mg], and potassium [K]) increased at higher soil acidity, while the two mobile fractions (water- and acid-soluble) of acidic metals—potentially phytotoxic aluminium (Al), cadmium (Cd) and manganese (Mn)—were significantly enhanced on very acid soils. The current paper presents an investigation of soil-wood chemistry relationships with basal area tree growth. It was hypothesized that the growth of sugar maple would be reduced by low base cation and high acidic metal concentrations in the xylem mobile fractions. Sugar maple trees (n = 55) from six watersheds in southern Quebec, Canada were analysed by sequential chemical extractions for the water-soluble, acid-soluble and residual fractions of base cations (Ca, K, Mg) and acidic metals (Al, Cd, Mn) in xylem. Generally, tree growth was positively correlated to concentrations of base cations in wood (ρ = 0.27-0.50) and soil (ρ = 0.41-0.67), and negatively correlated to concentrations of acidic metals in wood (ρ = −0.33 to −0.52) and soil (ρ = −0.67). However, these relations differed depending on the element fraction considered. Water- and acid-soluble xylem concentrations of base cations and Al were among the best predictors of growth trends (R² = 0.46-0.51). The relationship between acidic metals and tree growth is further discussed.     

盐度与滤料量对生物膜降氨氮作用的影响

淡水中培养的生物膜,去氨氮能力随盐度上升及升盐速率的增加而逐渐下降,当盐度由0.6升至13.3、23.9和31.3并稳定48 h后,氨氮去除率分别为100%、93.0%和86.9%;当按不同的速度降盐至淡水环境时,生物膜去氨氮的能力逐步得以恢复,特别是降到淡水时,去氨氮率均达90%以上,基本达到淡水中生物膜去氨氮的能力。经24~36 h的吸附作用,沸石对氨氮的吸附能力强于瓷质生化环,生化环48 h去氨氮的能力(95.1%)接近沸石(100%)。以沸石为滤料的滤器去氨氮能力与速率随沸石用量增加而增强。24 h内天然沸石吸附作用去氨氮能力强于生物沸石,生物沸石48 h对氨氮的去除率(99.2%)略超过天然沸石(95.2%)。     

不同生境祁连圆柏径向生长对气候变化的响应

通过在青海都兰曲什岗地区建立不同生境的祁连圆柏树轮宽度年表及分析,揭示了不同微环境下祁连圆柏的径向生长对气候变化的响应。从标准轮宽年表的统计特征来看,森林中部年表的平均敏感度、标准差以及序列间的相关系数等统计量均高于其他地点,而凹地年表的上述统计量都较低;各序列之间的相关分析表明,无论在高频变化还是在低频变化上,森林上限年表与其他各采样点的年表均存在较大差异,这种差异在低频变化上尤为明显;采样点轮宽年表与气候资料的相关分析表明,森林中部、下限及水分条件相对较好的凹地,树木径向生长主要与当年6月份降水量之间存在显著的正相关关系,而与同期月平均最高温度之间存在显著的负相关关系。值得提出的是,森林上限祁连圆柏的径向生长与当年7月份温度之间存在极显著的正相关关系。该研究所揭示的不同生境树木生长特性及其对气候响应的差异,一方面对于模拟不同微环境下树木生长对全球变化的响应具有重要意义,另一方面对于利用同一地区的树轮资料重建不同气候要素提供了依据。      

圆柱形薄壳压力管道的内力分析

本文从分析具有刚性环的圆柱形薄壳,承受内压力时在刚性环附近产生的局部性的弯矩和剪力,从而论证同类型的压力容器为何多在环向焊缝附近并沿环向爆裂的原因所在。